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Brodzinski, R. L., H. S. Miley, J. H. Reeves, and F. T. Avignone. "Ultra-low background germanium spectrometry: Techniques and results." Nuclear Physics B - Proceedings Supplements 28, no. 1 (July 1992): 415–19. http://dx.doi.org/10.1016/0920-5632(92)90206-8.
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Pacult, Mark A., Corey T. Walker, Jakub Godzik, Jay D. Turner, and Juan S. Uribe. "Emerging Technologies in Spinal Surgery: Ultra-Low Radiation Imaging Platforms." Operative Neurosurgery 21, Supplement_1 (June 15, 2021): S39—S45. http://dx.doi.org/10.1093/ons/opaa324.
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Abstract BACKGROUND Spine surgery has seen tremendous growth in the past 2 decades. A variety of safety, practical, and market-driven needs have spurred the development of new imaging technologies as necessary tools for modern-day spine surgery. Although current imaging techniques have proven satisfactory for operative needs, it is well-known that these techniques have negative consequences for operators and patients in terms of radiation risk. Several mitigating techniques have arisen in recent years, ranging from lead protection to radiation-reducing protocols, although each technique has limits. A hitherto-problematic barrier has been the fact that efforts to diminish radiation emission come at the cost of reduced image quality. OBJECTIVE To describe new ultra-low radiation imaging modalities that have the potential to drastically reduce radiation risk and minimize unacceptable adverse effects. METHODS A literature review was performed of articles and studies that used either of 2 ultra-low radiation imaging modalities, the EOS system (EOS-Imaging S.A., Paris, France) and LessRay (NuVasive, San Diego, CA). RESULTS Both ultra-low radiation imaging modalities reduce radiation exposure in the preoperative and perioperative settings. EOS provides 3-dimensional reconstructive capability, and LessRay offers intraoperative tools that facilitate spinal localization and proper visual alignment of the spine. CONCLUSION These novel radiation-reducing technologies diminish patient and surgeon exposure, aid the surgeon in preoperative planning, and streamline intraoperative workflow.
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Laubenstein, Matthias. "Screening of materials with high purity germanium detectors at the Laboratori Nazionali del Gran Sasso." International Journal of Modern Physics A 32, no. 30 (October 30, 2017): 1743002. http://dx.doi.org/10.1142/s0217751x17430023.
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The Gran Sasso National Laboratories (LNGS) of the National Institute of Nuclear Physics (INFN) are equipped with an underground ultra-low background facility namely the SubTErranean Low Level Assay (STELLA), which is in first line dedicated to material screening for the fundamental physics experiments installed in the underground laboratories. The high level of performance of the ultra-low-level detector systems allows for detecting extremely low radioactivity levels in materials down to the [Formula: see text] level. The installations and experimental setups using ultra-low background techniques will be described shortly, and an example of material screening will be discussed.
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Tsuyoshi, YOSHIHARA, and FUJITA Satoshi. "Towards Fog-Assisted Virtual Reality MMOG with Ultra-Low Latency." International journal of Computer Networks & Communications 12, no. 6 (November 30, 2020): 33–47. http://dx.doi.org/10.5121/ijcnc.2020.12603.
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In this paper, we propose a method to realize a virtual reality MMOG (Massively Multiplayer Online Video Game) with ultra-low latency. The basic idea of the proposed method is to introduce a layer consisting of several fog nodes between clients and cloud server to offload a part of the rendering task which is conducted by the cloud server in conventional cloud games. We examine three techniques to reduce the latency in such a fog-assisted cloud game: 1) To maintain the consistency of the virtual game space, collision detection of virtual objects is conducted by the cloud server in a centralized manner; 2) To reflect subtle changes of the line of sight to the 3D game view, each client is assigned to a fog node and the head motion of the player acquired through HMD (Head-Mounted Display) is directly sent to the corresponding fog node; and 3) To offload a part of the rendering task, we separate the rendering of the background view from that of the foreground view, and migrate the former to other nodes including the cloud server. The performance of the proposed method is evaluated by experiments with an AWS-based prototype system. It is confirmed that the proposed techniques achieve the latency of 32.3 ms, which is 66 % faster than the conventional systems.
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Rumyantseva, N. S., and K. N. Gusev. "APPLICATION OF MODERN STRUCTURAL MATERIALS, METHODS AND DETECTORS FOR LOW-BACKGROUND EXPERIMENTS." Bulletin of Dubna International University for Nature, Society, and Man. Series: Natural and engineering sciences, no. 2 (47) (September 14, 2020): 29–35. http://dx.doi.org/10.37005/1818-0744-2020-2-29-35.
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Good examples of the key tasks of modern non-accelerator physics are the searches for dark matter and neutrinoless double beta decay. The essential requirement for such an experiment is the requirement of a minimal background level. The ways to reduce it are quite obvious and widely used in the ongoing experiments. So, the experiments are located in the underground laboratories, a careful selection of structural materials is carried out, and various techniques for active background suppression are used. However, in order to advance in new generation projects in addition to a serious increase in the detector mass, the significant reduction of the background level (which is already pretty low) is required. Very important irremovable background sources are the structural materials close to the detector(s). In this regard, it is extremely important not only to constantly search for new low-background materials, but also to ensure that radioactive contaminants cannot be introduced at the stage of the required parts production. In this article the results of the successful using of structural parts produced by modern methods from novel low-background materials during the preparation of the new generation ultra-low-background experiment searching for neutrinoless double beta decay are presented.
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Borlaff, Alejandro, Ignacio Trujillo, Javier Román, John E. Beckman, M. Carmen Eliche-Moral, Raúl Infante-Sáinz, Alejandro Lumbreras-Calle, et al. "The missing light of the Hubble Ultra Deep Field." Astronomy & Astrophysics 621 (January 2019): A133. http://dx.doi.org/10.1051/0004-6361/201834312.
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Context. The Hubble Ultra Deep field (HUDF) is the deepest region ever observed with the Hubble Space Telescope. With the main objective of unveiling the nature of galaxies up to z ∼ 7 − 8, the observing and reduction strategy have focused on the properties of small and unresolved objects, rather than the outskirts of the largest objects, which are usually over-subtracted. Aims. We aim to create a new set of WFC3 IR mosaics of the HUDF using novel techniques to preserve the properties of the low surface brightness regions. Methods. We created ABYSS: a pipeline that optimises the estimate and modelling of low-level systematic effects to obtain a robust background subtraction. We have improved four key points in the reduction: 1) creation of new absolute sky flat fields, 2) extended persistence models, 3) dedicated sky background subtraction and 4) robust co-adding. Results. The new mosaics successfully recover the low surface brightness structure removed on the previous HUDF published reductions. The amount of light recovered with a mean surface brightness dimmer than μ¯ = 26 mag arcsec−2 is equivalent to a m = 19 mag source when compared to the XDF and a m = 20 mag compared to the HUDF12. Conclusions. We present a set of techniques to reduce ultra-deep images (μ > 32.5 mag arcsec−2, 3σ in 10 × 10 arcsec boxes), that successfully allow us to detect the low surface brightness structure of extended sources on ultra deep surveys. The developed procedures are applicable to HST, JWST, EUCLID and many other space and ground-based observatories.
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Zykova, Marina, Mikhail Grishechkin, Andrew Khomyakov, Elena Mozhevitina, Roman Avetisov, Nadezda Surikova, Maxim Gromov, Alexander Chepurnov, Ivan Nikulin, and Igor Avetissov. "Hybrid Ultra-Low-Radioactive Material for Protecting Dark Matter Detector from Background Neutrons." Materials 14, no. 13 (July 5, 2021): 3757. http://dx.doi.org/10.3390/ma14133757.
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A laboratory technology for a new ultra-low background hybrid material (HM) which meets the requirements for neutron absorption with simultaneous neutron detection has been developed. The technology and hybrid material can be useful for future low background underground detectors designed to directly search for dark matter with liquid noble gases. The HM is based on a polymethylmethacrylate (PMMA) polymer matrix in which gadolinium nuclei are homogeneously distributed up to 1.5 wt% concentration in polymer slabs of 5 cm thickness. To determine the 65 impurity elements by the inductively coupled plasma mass-spectrometry (ICP-MS) technique in the Gd-based preparations in 100–0.01 ppb range, the corresponding method has been developed. Limits of determination (LD) of 0.011 ppb for uranium, and 0.016 ppb for thorium were achieved. An analysis of Gd raw materials showed that the lowest contents of U and Th (1.2–0.2 ppb) were detected in commercial Gd-based preparations. They were manufactured either from secondary raw materials (extraction phosphoric acid) or from mineral raw materials formed in sedimentary rocks (phosphogypsum). To produce the Gd-doped HM the commercial GdCl3 was purified and used for synthesis of low-background coordination compound, namely, acetylacetonate gadolinium (Gd(acac)3) with U/Th contents less than LD. When dissolving Gd(acac)3 in methylmethacrylate, the true solution was obtained and its further thermal polymerization allowed fabrication of the Gd-doped PMMA with ultra-low background.
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Simgen, Hardy, Gerd Heusser, Matthias Laubenstein, and Grzegorz Zuzel. "Analysis of radioactive trace impurities with μBq-sensitivity in Borexino." International Journal of Modern Physics A 29, no. 16 (June 17, 2014): 1442009. http://dx.doi.org/10.1142/s0217751x14420093.
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BOREXINO has set new standards in the field of ultra-low background experiments. Such a success was only possible by a strict quality control program during the construction phase of the experiment. In this paper, we describe how construction materials and auxiliary systems of the BOREXINO detector were screened for their residual radioactivity with unprecedented high sensitivity. The highly sensitive assay techniques developed for this purpose were also used to validate the purity of water and nitrogen used in the experiment. Moreover, we report on the production of 222 Rn -free nitrogen and synthetic air with very low 222 Rn concentration as well as on the successful search for commercial nitrogen with a particularly low concentration of argon and krypton.
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Evangelista, Luca, Bruno De Meo, Gianluca Bernabei, Gabriele Belloni, Giovanni D'Angelo, Marzio Vanzini, Laura Calzà, and Michele Gallamini. "Ultra-Low-Level Laser Therapy and Acupuncture Libralux: What Is so Special?" Medicines 6, no. 1 (March 14, 2019): 40. http://dx.doi.org/10.3390/medicines6010040.
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Background: Contrary to the most credited theories on laser therapy that see power/energy as the major factors to its effectiveness, a technique using an extremely low power/energy laser stimulation to treat musculoskeletal pain and dysfunction is proposed. The stimulus consists of a 20 s train of modulated pulses with an average power below 0.02 mW and is applied on sequences of acupuncture points selected according to the impaired segment of the patient’s body. Methods: Modifications on the extracellular soft tissue matrix and on the “fascia” were sonographically demonstrated. Laboratory and clinical tests confirmed the effectiveness. Results: Responses similar to those experienced in acupuncture were observed. The device—a CE Class IIa certified medical device named Libralux—affords a clinically proven effectiveness exceeding 80% in the treatment of musculoskeletal conditions and associated motor dysfunctions. An average of just three application sessions was generally sufficient to overcome the dysfunction. Conclusions: The development of the method is supported by over 20 years of R&D activities, with a range of experiments discussed in several papers published in indexed peer-reviewed journals. A few considerations regarding the possible physiological action mechanisms involved are proposed in this paper.
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Menendez, Maria I., Richard Moore, Katherine Binzel, Michael Friel, Jun Zhang, Rebecca Jackson, and Michael Knopp. "2516 Ultra-low Na18F tracer dosing for preclinical skeletal imaging enables new concepts in digital PET/CT." Journal of Clinical and Translational Science 2, S1 (June 2018): 34–35. http://dx.doi.org/10.1017/cts.2018.144.
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OBJECTIVES/SPECIFIC AIMS: The aim of this study was to assess the ultra-dose Na18F dPET protocol feasibility for skeleton imaging in a canine model with reduced radiation dose and preserved quantitative characteristics. We hypothesized that administering an ultra-low Na18F dose would provide suitable image quality while reducing subject’s exposure to radiation. METHODS/STUDY POPULATION: In total, 13 adult male beagles [weight (kg) mean±SD; 14.3±2.2] were scanned. The dogs were administered 3 different Na18F doses: 3 (standard dose/SD), 1 (low dose/LD), and 0.05 (ultra-low dose/ULD) mCi. Imaging started ≃45 minutes post injection for ≃ 33 minute total acquisition time. Covering the whole body, 11 bed positions, acquiring 120 (3 mCi) and 180 (1, 0.05 mCi) seconds per bed position. All imaging was performed on a digital photon counting system (Philips Vereos, pre-commercial release). PET list mode data were reconstructed using Time-of-flight with 4, 2, and 1 mm3 voxel volumes. Point spread function, and Gaussian filtering were applied. Two experienced blinded readers evaluated image sets overall quality, tissue characterization, and quality of background in the whole body skeleton. Three-dimensional (3D) regions of interest (ROI) were traced over the distal femur, first lumbar vertebra, and a portion of the liver, recording standard uptake values (SUVmax and SUVmean). RESULTS/ANTICIPATED RESULTS: All the scans and reconstructions were successfully completed in all subjects. Decreasing Na18F dose from the standard dose (3 mCi) to the ultra-low dose/ULDO (0.05 mCi), demonstrated acceptable image quality and quantification. Ultra-low dose Na18F SUVmean values for the 3D ROIs reported (mean±SD) 2.6±0.7, 2.5±1.1, 9±1.6, and 0.6±0.3 from the right and left distal femur, first lumbar vertebra, and a portion of the liver, respectively. When compared the SD with the LD and ULD, dPET demonstrated acceptable image quality and definition for qualitative overall assessment. This was also found for the overall quantitative ROI assessment of the healthy canine skeletons. DISCUSSION/SIGNIFICANCE OF IMPACT: Ultra-low dose Na18F at a level of 50 μCi for a 14 kg canine appears to be diagnostically feasible and a robust option to reduce (60-fold) radiotracer doses in a translational animal model using a dPET system. Furthermore, it allows us to move preclinical nuclear medicine imaging forward with substantial reduced exposure levels while preserving image quality. Both visual and quantitative results indicate that the standard-dose bone Na18F dPET can be decreased with a satisfactory diagnostic image quality. Ultra-low Na18F dose is indeed important for younger populations, control patients, and nononcological diseases/conditions. Favorable pharmacokinetics of Na18F (such as high bone uptake, minimal binding to serum proteins, rapid single-pass extraction, and fast clearance from the soft tissues) in addition to the technological capabilities of dPET/CT demonstrated feasibility enabling dose reduction strategies. Ultra-low dose has diagnostic reproducibility and lower radiation burden compared with higher fixed dose techniques in current available guidelines [Society of Nuclear Medicine and Molecular Imaging; SNMMI (5–10 mCi)]. Na18F dPET/CT provides higher sensitivity and diagnostic accuracy, which enables high-quality images with lower tracer activity in this translational animal model. Future research will apply the same methodology to other anatomical targets as well as to the use of different tracers. Preclinical nuclear medicine imaging using ultra-low tracer doses, demonstrated the potential to obtain reasonable quality images and diminishing radiation surveillance in accordance with as low as reasonably achievable tracer levels.
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Wang, Chen, Yao-Wu Shi, Lan-Xiang Zhu, Li-Fei Deng, Yi-Ran Shi, and De-Min Wang. "Auto-regressive moving average parameter estimation for 1/f process under colored Gaussian noise background." Journal of Algorithms & Computational Technology 13 (January 2019): 174830261986743. http://dx.doi.org/10.1177/1748302619867439.
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Current algorithms for estimating auto-regressive moving average parameters of transistor 1/f process are usually under noiseless background. Transistor noises are measured by a non-destructive cross-spectrum measurement technique, with transistor noise first passing through dual-channel ultra-low noise amplifiers, then inputting the weak signals into data acquisition card. The data acquisition card collects the voltage signals and outputs the amplified noise for further analysis. According to our studies, the output transistor 1/f noise can be characterized more accurately as non-Gaussian α-stable distribution rather than Gaussian distribution. We define and consistently estimate the samples normalized cross-correlations of linear SαS processes, and propose a samples normalized cross-correlations-based auto-regressive moving average parameter estimation method effective in noisy environments. Simulation results of auto-regressive moving average parameter estimation exhibit good performance.
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Maher, Anthony D., Prasad Patki, John C. Lindon, Elizabeth J. Want, Elaine Holmes, Michael Craggs, and Jeremy K. Nicholson. "Seminal Oligouridinosis: Low Uridine Secretion as a Biomarker for Infertility in Spinal Neurotrauma." Clinical Chemistry 54, no. 12 (December 1, 2008): 2063–66. http://dx.doi.org/10.1373/clinchem.2008.112219.
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Abstract Background: Compromised sexual health is a major rehabilitative barrier for men with lower–spinal cord injury (SCI). Although studies have revealed decreased sperm motility, the quantitative biochemical changes that underlie the infertility mechanism remain poorly understood. Methods: We employed a nontargeted approach combining 800 MHz hydrogen nuclear magnetic resonance (1H NMR) spectroscopy and ultra-performance liquid chromatography–mass spectrometry (UPLC-MS) with pattern recognition methods to analyze seminal fluid metabolite profiles in 10 men with and 8 without SCI above thoracic vertebra 10 (T10). Results: The metabolic phenotype for SCI could be predicted from the 1H NMR data. The median concentration of uridine in fertile controls was 1.55 mmol/L (range 1.0–5.0 mmol/L), but was undetectable by both NMR and MS in all but 2 individuals from the SCI group, one who later fathered a child without assisted fertility techniques. Conclusions: We hypothesize that uridine is likely to be an essential precursor to metabolites required for capacitation and is a potential marker for the prognosis of post-SCI functional fertility recovery. We derived the term “seminal oligouridinosis” to describe this newly identified condition.
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Ferrer, Pilar, Juan Rubio-Zuazo, Catherine Heyman, Fatima Esteban-Betegón, and Germán R. Castro. "Multi-use high/low-temperature and pressure compatible portable chamber forin situgrazing-incidence X-ray scattering studies." Journal of Synchrotron Radiation 20, no. 3 (March 1, 2013): 474–81. http://dx.doi.org/10.1107/s0909049513002598.
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The multipurpose portable ultra-high-vacuum-compatible chamber described in detail in this article has been designed to carry out grazing-incidence X-ray scattering techniques on the BM25-SpLine CRG beamline at the ESRF. The chamber has a cylindrical form, built on a 360° beryllium double-ended conflate flange (CF) nipple. The main advantage of this chamber design is the wide sample temperature range, which may be varied between 60 and 1000 K. Other advantages of using a cylinder are that the wall thickness is reduced to a minimum value, keeping maximal solid angle accessibility and keeping wall absorption of the incoming X-ray beam constant. The heat exchanger is a customized compact liquid-nitrogen (LN2) continuous-flow cryostat. LN2 is transferred from a storage Dewar through a vacuum-isolated transfer line to the heat exchanger. The sample is mounted on a molybdenum support on the heat exchanger, which is equipped with a BORALECTRIC heater element. The chamber versatility extends to the operating pressure, ranging from ultra-high vacuum (<10−10 mbar) to high pressure (up to 3 × 103 mbar). In addition, it is equipped with several CF ports to allocate auxiliary components such as capillary gas-inlet, viewports, leak valves, ion gun, turbo pump,etc., responding to a large variety of experiment requirements. A movable slits set-up has been foreseen to reduce the background and diffuse scattering produced at the beryllium wall. Diffraction data can be recorded either with a point detector or with a bi-dimensional CCD detector, or both detectors simultaneously. The system has been designed to carry out a multitude of experiments in a large variety of environments. The system feasibility is demonstrated by showing temperature-dependence grazing-incidence X-ray diffraction and conductivity measurements on a 20 nm-thick La0.7Ca0.3MnO3thin film grown on a SrTiO3(001) substrate.
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Millholland, John M., Shuqiang Li, Cecilia A. Fernandez, and Anthony P. Shuber. "Detection of low-frequency FGFR3 mutations in the urine of patients with bladder cancer using next-generation deep sequencing." Journal of Clinical Oncology 30, no. 30_suppl (October 20, 2012): 59. http://dx.doi.org/10.1200/jco.2012.30.30_suppl.59.
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59 Background: FGFR3 mutations have been identified in ~60-70% of low-stage, non-invasive tumors. Our group and others have developed assays to detect FGFR3 mutations in the urine of bladder cancer patients. However, urine-based assays have been limited by the technical ability to detect rare events in a dilute medium where there is a high background of normal DNA. In these assays, FGFR3 mutations are generally found in ~30% of the urine samples, which is < 50% concordance with the expected detection in tissue. We have now developed an ultra-deep amplicon sequencing technique that increases FGFR3 mutation detection in urine to ~67%, close to the expected detection frequency if every mutation found in tissue could be detected in urine. Methods: Amplicons were designed against FGFR3 exons 7, 10, and 15 using PCR primers containing the adapter sequences for unidirectional sequencing. Primary amplification was performed from DNA isolated from 4 ml of urine. The resulting PCR products were used as template for emulsion PCR and these were then sequenced using the Roche 454 GS Junior. Samples were analyzed for total DNA reads per sample and number of mutant sequencing reads to determine percent mutation. Results: Urine samples from 43 patients with bladder cancer were analyzed by both our previously described qPCR method and the new ultra-deep sequencing approach. Using ultra-deep amplicon sequencing, 24 out of 43 (55.8%) were positive for FGFR3 mutations, while only 5 out of 43 (11.6%) were positive for mutations by qPCR. The urine samples from the 15 newly identified mutations using deep sequencing contained FGFR3 mutations as low as 0.05% mutant DNA. The sensitivity achieved using deep sequencing was 91% concordant with the FGFR3 mutations observed in tissue. Conclusions: We have developed a highly sensitive non-invasive urine based assay that can detect FGFR3 mutant DNA when present at < 1% of the sample and is > 90% concordance with the mutations found in tumor tissues. To our knowledge, this is the first practical application of next generation sequencing technology for diagnostic use.
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Irina, Zhigacheva, Volodkin Aleksandr, and Rasulov Maksud. "The Influence of Ultra-Low Concentrations of Potassium Anphen on the Bioenergetic Characteristics of Mitochondria." Current Bioactive Compounds 16, no. 4 (June 19, 2020): 537–42. http://dx.doi.org/10.2174/1573407214666181116093909.
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Background: One of the main sources of ROS in stress conditions is the mitochondria. Excessive generation of ROS leads to oxidation of thiol groups of proteins, peroxidation of membrane lipids and swelling of the mitochondria. In this regard, there is a need to search for preparationsadaptogens that increase the body's resistance to stress factors. Perhaps, antioxidants can serve as such adaptogens. This work aims at studying the effect of antioxidant; the potassium anphen in a wide range of concentrations on the functional state of 6 day etiolated pea seedlings mitochondria (Pisum sativum L). Methods: The functional state of mitochondria was studied per rates of mitochondria respiration, by the level of lipid peroxidation and study of fatty acid composition of mitochondrial membranes by chromatography technique. Results: Potassium anphen in concentrations of 10-5 - 10-8 M and 10-13-10-16 prevented the activation of LPO in the mitochondrial membranes of pea seedlings, increased the oxidation rates of NAD-dependent substrates and succinate in the respiratory chain of mitochondria that probably pointed to the anti-stress properties of the drug. Indeed, the treatment of pea seeds with the preparation in concentrations of 10-13 M prevented the inhibition of growth of seedlings in conditions of water deficiency. Conclusion: It is assumed that the dose dependence of the biological effects of potassium anphen and the manifestation of these effects in ultra-low concentrations are due to its ability in water solutions to form a hydrate containing molecular ensembles (structures).
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Wang, Haiping, Dongbo Mi, Wanxu Wang, Hongliang Zhang, Dongsheng Tong, Shengjiang Wang, and Feng Gao. "Latent Fingerprint Visualization and Subsequent DNA Extraction Using Electron Beam Evaporation of Metallic Ultra-Thin Films." Current Nanoscience 15, no. 3 (February 19, 2019): 248–53. http://dx.doi.org/10.2174/1573413714666180628155824.
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Background: Proper detection and subsequent extraction of biological evidence are crucial for crime scene reconstruction. Vacuum metal deposition is currently an effective technique used in latent fingerprint development. However, the established procedures commonly undergo a direct plasma bombardment, a high ablation fluence and/or a high temperature process in vacuum metal deposition system. Method: In this work, electron beam evaporation (EBE) was used to investigate the development of latent fingerprints and subsequent DNA extraction of biological evidence. Gold or copper is preferentially nucleated on the background surfaces rather than the fingerprint residues due to the difference of the nature of the surface, which indicates that the gold / copper and copper agglomerates are binding to the fingerprint valleys not the ridges of the fingerprint, revealing bright patterns with excellent ridge detail clarity on black surfaces. Result: It is demonstrated that the co-extraction of the latent fingerprints and DNA is attributed to electron beam evaporated one-step process with relatively low energy bombarding energetic species and neutral particles, less possibility of contamination and without toxic and fluorine-based gases. Conclusion: Our results demonstrate that EBE is a promising technique for the latent fingerprints and DNA co-extraction.
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Barbosa, Laila R. A., Emanuelle L. da Silva, Anne C. G. de Almeida, Yanka E. A. R. Salazar, André M. Siqueira, Maria das Graças Costa Alecrim, José Luiz Fernandes Vieira, et al. "An Ultra-Sensitive Technique: Using Pv-mtCOX1 qPCR to Detect Early Recurrences of Plasmodium vivax in Patients in the Brazilian Amazon." Pathogens 10, no. 1 (December 30, 2020): 19. http://dx.doi.org/10.3390/pathogens10010019.
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Background: Early recurrence of Plasmodium vivax is a challenge for malaria control in the field, particularly because this species is associated with lower parasitemia, which hinders diagnosis and monitoring through blood smear testing. Early recurrences, defined as the persistence of parasites in the peripheral blood despite adequate drug dosages, may arise from resistance to chloroquine. The objective of the study was to estimate early recurrence of P. vivax in the Brazilian Amazon by using a highly-sensitive detection method, in this case, PCR. Methods: An ultra-sensitive qPCR that targeted mitochondrial DNA was used to compare a standard qPCR that targeted 18S rDNA to detect early recurrence of P. vivax in very low densities in samples from patients treated with chloroquine. Results: Out of a total of 312 cases, 29 samples (9.3%) were characterized as recurrences, from which 3.2% (10/312) were only detected through ultra-sensitive qPCR testing. Conclusions: Studies that report the detection of P. vivax early recurrences using light microscopy may severely underestimate their true incidence.
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Polach, Henry. "Liquid Scintillation 14C Spectrometry: Errors and Assurances." Radiocarbon 31, no. 03 (1989): 327–31. http://dx.doi.org/10.1017/s0033822200011875.
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Liquid scintillation (LS) 14C spectrometry, using ultra low-level, high-efficiency and resolution α and β particle detection equipment is seen as an excellent tool supporting future 14C radiometry. Modern technology ensures electronic excellence: high-precision, small-sample (100mg) dating ability, flexibility of use for the detection of α and β particle emitting radioisotopes at and below natural abundance levels. Multiple applications to environmental research, supported by elegant software and commercial availability, are its attributes. However, mastering the new technology takes time as lessons learned in gas-proportional 14C radiometry and high-background counting are not directly applicable to ultra low-level 14C LS spectrometry using benzene as the counting medium. That discordant results can be obtained by any technique based on physical measurement is well established. This is demonstrated for 14C age determination by reference to an international cross-check organized by the University of Glasgow. Reasons for aberrations are explored and the question is raised if it is not timely to introduce the type of quality assurance practiced by other analytical disciplines. Better results will not only serve the daters and users but will generally enhance the value of worldwide 14C research.
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Dawood, Y., G. J. Strijkers, J. Limpens, R. J. Oostra, and B. S. de Bakker. "Novel imaging techniques to study postmortem human fetal anatomy: a systematic review on microfocus-CT and ultra-high-field MRI." European Radiology 30, no. 4 (December 13, 2019): 2280–92. http://dx.doi.org/10.1007/s00330-019-06543-8.
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Abstract Background MRI and CT have been extensively used to study fetal anatomy for research and diagnostic purposes, enabling minimally invasive autopsy and giving insight in human fetal development. Novel (contrast-enhanced) microfocus CT (micro-CT) and ultra-high-field (≥ 7.0 T) MRI (UHF-MRI) techniques now enable micron-level resolution that combats the disadvantages of low-field MRI and conventional CT. Thereby, they might be suitable to study fetal anatomy in high detail and, in time, contribute to the postmortem diagnosis of fetal conditions. Objectives (1) To systematically examine the usability of micro-CT and UHF-MRI to study postmortem human fetal anatomy, and (2) to analyze factors that govern success at each step of the specimen preparation and imaging. Method MEDLINE and EMBASE were systematically searched to identify publications on fetal imaging by micro-CT or UHF-MRI. Scanning protocols were summarized and best practices concerning specimen preparation and imaging were enumerated. Results Thirty-two publications reporting on micro-CT and UHF-MRI were included. The majority of the publications focused on imaging organs separately and seven publications focused on whole body imaging, demonstrating the possibility of visualization of small anatomical structures with a resolution well below 100 μm. When imaging soft tissues by micro-CT, the fetus should be stained by immersion in Lugol’s staining solution. Conclusion Micro-CT and UHF-MRI are both excellent imaging techniques to provide detailed images of gross anatomy of human fetuses. The present study offers an overview of the current best practices when using micro-CT and/or UHF-MRI to study fetal anatomy for clinical and research purposes. Key Points • Micro-CT and UHF-MRI can both be used to study postmortem human fetal anatomy for clinical and research purposes. • Micro-CT enables high-resolution imaging of fetal specimens in relatively short scanning time. However, tissue staining using a contrast solution is necessary to enable soft-tissue visualization. • UHF-MRI enables high-resolution imaging of fetal specimens, without the necessity of prior staining, but with the drawback of long scanning time.
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Fulk, George D., Stephanie A. Combs, Kelly A. Danks, Coby D. Nirider, Bhavana Raja, and Darcy S. Reisman. "Accuracy of 2 Activity Monitors in Detecting Steps in People With Stroke and Traumatic Brain Injury." Physical Therapy 94, no. 2 (February 1, 2014): 222–29. http://dx.doi.org/10.2522/ptj.20120525.
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Background Advances in sensor technologies and signal processing techniques provide a method to accurately measure walking activity in the home and community. Activity monitors geared toward consumer or patient use may be an alternative to more expensive monitors designed for research to measure stepping activity. Objective The objective of this study was to examine the accuracy of 2 consumer/patient activity monitors, the Fitbit Ultra and the Nike+ Fuelband, in identifying stepping activity in people with stroke and traumatic brain injury (TBI). Secondarily, the study sought to compare the accuracy of these 2 activity monitors with that of the StepWatch Activity Monitor (SAM) and a pedometer, the Yamax Digi-Walker SW-701 pedometer (YDWP). Design A cross-sectional design was used for this study. Method People with chronic stroke and TBI wore the 4 activity monitors while they performed the Two-Minute Walk Test (2MWT), during which they were videotaped. Activity monitor estimated steps taken were compared with actual steps taken counted from videotape. Accuracy and agreement between activity monitor estimated steps and actual steps were examined using intraclass correlation coefficients (ICC [2,1]) and the Bland-Altman method. Results The SAM demonstrated the greatest accuracy (ICC [2,1]=.97, mean difference between actual steps and SAM estimated steps=4.7 steps) followed by the Fitbit Ultra (ICC [2,1]=.73, mean difference between actual steps and Fitbit Ultra estimated steps=−9.7 steps), the YDWP (ICC [2,1]=.42, mean difference between actual steps and YDWP estimated steps=−28.8 steps), and the Nike+ Fuelband (ICC [2,1]=.20, mean difference between actual steps and Nike+ Fuelband estimated steps=−66.2 steps). Limitations Walking activity was measured over a short distance in a closed environment, and participants were high functioning ambulators, with a mean gait speed of 0.93 m/s. Conclusions The Fitbit Ultra may be a low-cost alternative to measure the stepping activity in level, predictable environments of people with stroke and TBI who can walk at speeds ≥0.58 m/s.
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Boldyreva, Liudmila. "A Theoretical Approach to Selection of a Biologically Active Substance in Ultra-Low Doses for Effective Action on a Biological System." Homeopathy 107, no. 02 (March 22, 2018): 137–42. http://dx.doi.org/10.1055/s-0038-1632362.
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Background and Aim An approach is offered to selecting a biologically active substance (BAS) in ultra-low dose for effective action on a biological system (BS). The technique is based on the assumption that BAS in ultra-low doses exerts action on BS by means of spin supercurrent emerging between the spin structure created by BAS, on the one hand, and the spin structure created by BS, on the other hand. According to modern quantum-mechanical concepts, these spin structures may be virtual particles pairs having precessing spin (that is, be essentially spin vortices in the physical vacuum) and created by the quantum entities that BAS and BS consist of. The action is effective provided there is equality of precession frequencies of spins in these spin structures. Method In this work, some methods are considered for determining the precession frequencies of spins in virtual particles pairs: (1) determination of energy levels of quantum entities that BS and BAS consist of; (2) the use of spin-flip effect of the virtual particles pair spin, the effect being initiated by action of magnetic vector potential (the spin-flip effect takes place when the varied frequency of the magnetic vector potential equals the precession frequency of the spin); (3) determining the frequencies of photons effectively acting on BS. Results and Conclusion It is shown that the effect of BAS in ultra-low doses on BS can be replaced by the effect of a beam of low-intensity photons, if the frequency of photons equals the precession frequency of spin in spin structures created by BS. Consequently, the color of bodies placed near a biological system is able to exert an effective action on the biological system: that is “color therapy” is possible. It is also supposed that the spin-flip effect may be used not only for determining the precession frequency of spin in spin structures created by BS but also for therapeutic action on biological systems.
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Liu, Jilong, Zu Liu, Shaomin Cheng, Fengming Guo, Meihua Tan, Jingjing Wang, Di Shao, et al. "VHVT: An ultra-sensitive somatic mutation detection and performance assessment program." Journal of Clinical Oncology 35, no. 15_suppl (May 20, 2017): 1588. http://dx.doi.org/10.1200/jco.2017.35.15_suppl.1588.
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1588 Background: NGS as a high throughput technique is particular valuable for cancer given its ability to detect multiple driver mutations. While reads contain SNVs and short InDels can be mapped to the right position using gatk-like programs, a program designed for germline mutation detection, reads contain long InDels such as EGFR EX19 deletions often wrongly mapped especially when deletions near the ends of the reads. Thus, gatk would not recognize these reads, consequently underestimate the mutation allelic frequency, and even missed out InDels when supporting reads were rare. Methods: Here we present a variation hotspot validation toolkit (VHVT), a validation based method to precisely detect the ultra-low frequency somatic mutations. As far as we know, it is the first specialized somatic mutation detection software. First, reference sequences aimed at the hotspot mutations were assembled, then reads were be mapped to the new assembled reference to precisely distinguish the supporting reads. Moreover, log odds (LOD) and Poisson mathematical model were integrated to control sequencing error, as a result, VHVT can achieve a limitation of detection at 0.01% with sensitivity and specificity above 95% and 99% respectively. In addition, we developed a method to quantitatively assess the performance of variation detection program using standard reference data. By mapping to the reconstructed reference, all supporting reads will be detected in sequencing data, and comparing theses with the number of supporting reads delivered by a program we can define recognition ratio of supporting reads. Results: Our reference standard data showed that VHVT can recognize average 30% more support reads than gatk for EGFR EX19 deletions. In a total 498 NSCLC clinical samples test, VHVT detected actionable mutations in 289 samples. 243 positive mutations were verified (168 by SANGER sequencing, 75 by ddPCR) with concordance rate at 100%. Conclusions: Taken all together, our results demonstrated the robust performance of VHVT for somatic mutation detection and program assessment and thus facilitate the development of personalized cancer therapy.
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Rabiee, Navid, Moein Safarkhani, and Mohammad Rabiee. "Rapid Electrochemical Ultra-Sensitive Evaluation and Determination of Daptomycin Based on Continuous Cyclic Voltammetry." Current Pharmaceutical Analysis 16, no. 2 (January 23, 2020): 181–85. http://dx.doi.org/10.2174/1573412914666181017134015.
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Background: In this work, a novel and extra sensitive blood sample determination method for on-line monitoring of Daptomycin is represented. Materials and Methods: This technique is in accordance with the electro-membrane extraction (EME) and stripping fast Fourier transform continuous cyclic voltammetry (SFFTCCV) coupling. Briefly, the potential waveform had become constantly utilized over a Gold Electrode and the electrode impulse was acquired by taking away the base current and developing the current in the particular potential area of oxidation of sample. Results: This method was performed by utilizing a DC potential and migration of Daptomycin from the analyte fluid to the layer of 4-methyl-2-pentanol as well as following migration to the acceptor fluid. Conclusion: A low and valuable detection limit of 3.5 ng ml-1 and quantification limit of 10.2 ng ml-1 are considered as a part of the sensible results of this experiment. Furthermore, efficient linearity in the range of 10.0-600 ng ml-1 was observed.
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Whalley, Celina, Karl Payne, Enric Domingo, Andrew Blake, Susan Richman, Jill Brooks, Nikolaos Batis, et al. "Ultra-Low DNA Input into Whole Genome Methylation Assays and Detection of Oncogenic Methylation and Copy Number Variants in Circulating Tumour DNA." Epigenomes 5, no. 1 (February 19, 2021): 6. http://dx.doi.org/10.3390/epigenomes5010006.
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Background: Abnormal CpG methylation in cancer is ubiquitous and generally detected in tumour specimens using a variety of techniques at a resolution encompassing single CpG loci to genome wide coverage. Analysis of samples with very low DNA inputs, such as formalin fixed (FFPE) biopsy specimens from clinical trials or circulating tumour DNA is challenging at the genome-wide level because of lack of available input. We present the results of low input experiments into the Illumina Infinium HD methylation assay on FFPE specimens and ctDNA samples. Methods: For all experiments, the Infinium HD assay for methylation was used. In total, forty-eight FFPE specimens were used at varying concentrations (lowest input 50 ng); eighteen blood derived specimens (lowest input 10 ng) and six matched ctDNA input (lowest input 10 ng)/fresh tumour specimens (lowest input 250 ng) were processed. Downstream analysis was performed in R/Bioconductor for quality control metrics and differential methylation analysis as well as copy number calls. Results: Correlation coefficients for CpG methylation were high at the probe level averaged R2 = 0.99 for blood derived samples and R2 > 0.96 for the FFPE samples. When matched ctDNA/fresh tumour samples were compared, R2 > 0.91 between the two. Results of differential methylation analysis did not vary significantly by DNA input in either the blood or FFPE groups. There were differences seen in the ctDNA group as compared to their paired tumour sample, possibly because of enrichment for tumour material without contaminating normal. Copy number variants observed in the tumour were generally also seen in the paired ctDNA sample with good concordance via DQ plot. Conclusions: The Illumina Infinium HD methylation assay can robustly detect methylation across a range of sample types, including ctDNA, down to an input of 10 ng. It can also reliably detect oncogenic methylation changes and copy number variants in ctDNA. These findings demonstrate that these samples can now be accessed by methylation array technology, allowing analysis of these important sample types.
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Rahman, Mustafizur. "Special Issue on Micro/Nano Machining – Processes, Systems and Control." International Journal of Automation Technology 5, no. 1 (January 5, 2011): 3. http://dx.doi.org/10.20965/ijat.2011.p0003.
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In recent years, the trend in miniaturization of products is pervasive in areas such as information technology, biotechnology, environmental and medical industries. Micro-machining is the key supporting technology that has to be developed to meet the challenges posed by the requirements of product miniaturization and industrial realization of nanotechnology. Micro-machining techniques can be carried out by techniques based on energy beams (beam-based micro-machining) or solid cutting tools (tool-based micro-machining). Beambased micro-machining have some limitations due to poor control of 3D structures, low material removal rate and low aspect ratio. Moreover, these processes require special facilities and the maximum achievable thickness is relatively small. Some of these limitations can be overcome by tool-based micro-machining techniques using ultra precision machine tools and solid tools used as cutting elements to produce the micro-features with well controlled shape and tolerances. Tool-based micro-machining techniques essentially include precision machining processes as turning, milling, grinding and electrical discharge machining (EDM), whereby material removal is done at the micron level. The advantages of such processes are that almost every material such as metals, plastics and semiconductors can be machined with no limitation in machining shapes. Recently, combinations of conventional material removal processes, such as turning and milling, have been hybridized with non-conventional machining processes like EDM and EDG to fabricate micro-structures with high dimensional accuracy. In order to achieve meaningful implementation of compound micro-machining techniques three important areas are required to be addressed. These are: development of machine tools capable of performing compound micro-machining (i.e. micro turning, micro milling, micro EDM, etc. on the same machine and setup), understanding of process physics to provide relevant background for modeling,measurement, identification of control parameters and application of feedback control in order to control compound and hybrid manufacturing processes and development of compound and hybrid processes. An integrated effort in these areas is needed for successful implementation of tool-based micro-machining. An attempt has been made in this special issue to highlight latest articles on these areas. I would like to express my sincere appreciation to the authors, reviewers and editors for their invaluable contributions for this issue.
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Saifollahi, Teymoor, Joachim Janz, Reynier F. Peletier, Michele Cantiello, Michael Hilker, Steffen Mieske, Edwin A. Valentijn, Aku Venhola, and Gijs Verdoes Kleijn. "Ultra-compact dwarfs beyond the centre of the Fornax galaxy cluster: hints of UCD formation in low-density environments." Monthly Notices of the Royal Astronomical Society 504, no. 3 (April 21, 2021): 3580–609. http://dx.doi.org/10.1093/mnras/stab1118.
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ABSTRACT Ultra-compact dwarf galaxies (UCDs) were serendipitously discovered by spectroscopic surveys in the Fornax cluster 20 yr ago. Nowadays, it is commonly accepted that many bright UCDs are the nuclei of galaxies that have been stripped. However, this conclusion might be driven by biased samples of UCDs in high-density environments, on which most searches are based. With the deep optical images of the Fornax Deep Survey, combined with public near-infrared data, we revisit the UCD population of the Fornax cluster and search for UCD candidates, for the first time, systematically out to the virial radius of the galaxy cluster. Our search is complete down to magnitude mg = 21 mag or M$_g\, \sim$ −10.5 mag at the distance of the Fornax cluster. The UCD candidates are identified and separated from foreground stars and background galaxies by their optical and near-infrared colours. This primarily utilizes the u−i/i−Ks diagram and a machine learning technique is employed to incorporate other colour combinations to reduce the number of contaminants. The newly identified candidates (44) in addition to the spectroscopically confirmed UCDs (61), increase the number of known Fornax UCD considerably (105). Almost all of the new UCD candidates are located outside the Fornax cluster core (360 kpc), where all of the known UCDs were found. The distribution of UCDs within the Fornax cluster shows that a population of UCDs may form in low-density environments. This most likely challenges the current models of UCD formation.
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Millholland, John M., Shuqiang Li, Cecilia A. Fernandez, and Anthony P. Shuber. "Use of next-generation deep sequencing to improve FGFR3 mutation detection in the urine of patients with bladder cancer." Journal of Clinical Oncology 30, no. 5_suppl (February 10, 2012): 289. http://dx.doi.org/10.1200/jco.2012.30.5_suppl.289.
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289 Background: FGFR3 mutations have been identified in ∼60-70% of low-stage, non-invasive tumors. Our group and others have developed assays to detect FGFR3 mutations in the urine of bladder cancer patients. However, urine-based assays have been limited by the technical ability to detect rare events in a dilute medium where there is a high background of normal DNA. In these assays, FGFR3 mutations are generally found in ∼30% of the urine samples, which is < 50% concordance with the expected detection in tissue. We have now developed an ultra-deep amplicon sequencing technique that increases FGFR3 mutation detection in urine to ∼67%, near the expected detection if every mutation found in tissue could be detected in urine. Methods: Amplicons were designed against FGFR3 exons 7, 10, and 15 using PCR primers containing the adapter sequences for unidirectional sequencing. Taqman probes were used to determine if sufficient DNA was present in each sample. Primary amplification was performed from DNA isolated from 4 ml of urine. The resulting PCR products were used as template for emulsion PCR and these were then sequenced using the Roche 454 GS Junior. Samples were analyzed for total DNA reads per sample and number of mutant sequencing reads to determine percent mutation. Results: Urine samples from 29 patients with stage Ta bladder cancer were analyzed by both our previously described qPCR method and the new ultra-deep sequencing approach. Of the 29 samples, 2 did not have sufficient DNA for analysis by sequencing. Using ultra-deep amplicon sequencing, 18 out of 27 (66.7%) were positive for FGFR3 mutations, while only 3 out of 27 (11.1%) were positive for mutations by qPCR. The urine samples from the 15 newly identified mutations using deep sequencing contained FGFR3 mutations as low as 0.05%. The sensitivity achieved using deep sequencing approximates the FGFR3 mutations observed in tissue. Conclusions: We have developed a highly sensitive non-invasive urine based assay that can detect FGFR3 mutant DNA when present at < 1% of the sample and suggests > 90% concordance with the expected mutations in Ta tumor tissues. To our knowledge, this is the first practical application of next generation sequencing technology for diagnostic use.
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Noël, Peter B., Stephan Engels, Thomas Köhler, Daniela Muenzel, Daniela Franz, Michael Rasper, Ernst J. Rummeny, Martin Dobritz, and Alexander A. Fingerle. "Evaluation of an iterative model-based CT reconstruction algorithm by intra-patient comparison of standard and ultra-low-dose examinations." Acta Radiologica 59, no. 10 (January 10, 2018): 1225–31. http://dx.doi.org/10.1177/0284185117752551.
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Background The explosive growth of computer tomography (CT) has led to a growing public health concern about patient and population radiation dose. A recently introduced technique for dose reduction, which can be combined with tube-current modulation, over-beam reduction, and organ-specific dose reduction, is iterative reconstruction (IR). Purpose To evaluate the quality, at different radiation dose levels, of three reconstruction algorithms for diagnostics of patients with proven liver metastases under tumor follow-up. Material and Methods A total of 40 thorax–abdomen–pelvis CT examinations acquired from 20 patients in a tumor follow-up were included. All patients were imaged using the standard-dose and a specific low-dose CT protocol. Reconstructed slices were generated by using three different reconstruction algorithms: a classical filtered back projection (FBP); a first-generation iterative noise-reduction algorithm (iDose4); and a next generation model-based IR algorithm (IMR). Results The overall detection of liver lesions tended to be higher with the IMR algorithm than with FBP or iDose4. The IMR dataset at standard dose yielded the highest overall detectability, while the low-dose FBP dataset showed the lowest detectability. For the low-dose protocols, a significantly improved detectability of the liver lesion can be reported compared to FBP or iDose4 ( P = 0.01). The radiation dose decreased by an approximate factor of 5 between the standard-dose and the low-dose protocol. Conclusion The latest generation of IR algorithms significantly improved the diagnostic image quality and provided virtually noise-free images for ultra-low-dose CT imaging.
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Marchegiani, Francesca, Francesco Ferella, and Stefano Nisi. "Material Screening with Mass Spectrometry." Physics 3, no. 1 (February 15, 2021): 71–84. http://dx.doi.org/10.3390/physics3010007.
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Inductively coupled plasma mass spectrometry is a powerful analytical technique. Because of its sensitivity, accuracy, multielement capability, high throughput, rapid analysis times and low detection limits, it is able to determine simultaneously long-lived radionuclides at trace and ultra-trace levels as well as isotope ratios. It has been increasingly applied in the framework of rare events experiments like those investigating the nature of dark matter and neutrinos, where the screening and selection of extremely radiopure materials for the experimental apparatus is crucial. Here, the inductively coupled plasma mass spectrometry (ICP-MS) measurements of the chemical purity of a Cs2HfCl6 crystal scintillator used to study α decay of naturally occurring Hf isotopes and its own raw materials are reported. Moreover, in the framework of the GERDA/LEGEND experiment, an overview of the ICP-MS results to monitor the recycling process of enriched germanium scraps is shown. Significant outcomes, such as low detection limits despite the small amount of sample to analyze and fast ICP-MS results, have been achieved in response to the challenges required by modern low background experiments.
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Crafa, Francesco, Sebastian Smolarek, Giulia Missori, Mostafa Shalaby, Silvia Quaresima, Adele Noviello, Diletta Cassini, et al. "Transanal Inspection and Management of Low Colorectal Anastomosis Performed With a New Technique: the TICRANT Study." Surgical Innovation 24, no. 5 (May 17, 2017): 483–91. http://dx.doi.org/10.1177/1553350617709182.
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Background: Anastomotic leakage is one of the most serious complications after rectal cancer surgery. Method: A prospective multicenter interventional study to assess a newly described technique of creating the colorectal and coloanal anastomosis. The primary outcome was to access the safety and efficacy of this technique in the reduction of anastomotic leak. Result: Fifty-three patients with rectal cancer who underwent low or ultra-low anterior resection were included in the study. There were 35 males and 18 females, with a median age of 68 years (range = 49-89 years). The median tumor distance from the anal verge was 8 cm (range = 4-12 cm), and the median body mass index was 24 kg/m2 (range = 20-35 kg/m2). Thirty patients underwent open, 16 laparoscopic, and 7 robotic surgeries. Multiple firing (2-charges) was required in 30 patients to obtain a complete rectal division. Forty-five patients had colorectal anastomosis, and 8 patients had coloanal anastomosis. The protective ileostomy was created in 40 patients at the time of initial surgery. There was no mortality in the first 30 days postoperatively, and only 10 (19%) patients developed complications. There were 3 anastomotic leakages (6%); 2 of them were subclinical with ileostomy created at initial operation and both were treated conservatively with transanal drainage and intravenous antibiotics. One patient required reoperation and ileostomy. The median length of hospital stay was 10 days (range = 4-20 days). Conclusion: Our technique is a safe and efficient method of creation of colorectal anastomosis. It is also a universal method that can be used in open, laparoscopic, and robotic surgeries.
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Rouanet, P., M. Rivoire, B. Lelong, E. Rullier, F. Dravet, L. Mineur, L. Vanseymortier, et al. "Sphincter preserving surgery after preoperative treatment for ultra-low rectal carcinoma. A French multicenter prospective trial: GRECCAR 1." Journal of Clinical Oncology 24, no. 18_suppl (June 20, 2006): 3527. http://dx.doi.org/10.1200/jco.2006.24.18_suppl.3527.
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3527 Background: GRECCAR 1 is a phase III randomised multicenter trial which compared two preoperative treatments for low rectal carcinoma which should be classicaly treated by abdominoperineal resection (Eligibility: distance between the tumor [T] and the levator ani [LA] less than 2 cm). Methods: Between 2001 and 2005, 207 patients with rectal adenocarcinomas were included in 13 French centers. The average distance between the tumor and the levator ani was 0.8 cm. 72% of the tumors were classified T3 with 60% of N1 on pre treatment endorectal ultrasonography. The mean lenght of the tumors was 5 cm on colonoscopy. Preoperative treatment randomisation was made between high dose radiation (HDR: 45 + 18 Gy: 106 patients) and radio-chemotherapy (RTCT: 45 Gy + 5FU continuous infusion: 101 patients). All surgeons performed homogeous technique for intersphincteric resection. Results: Conservative rate was 83% (HDR) and 86% (RTCT) (p: 0.64) with 84% (140/168) of intersphincteric resection. Conservative rate did not differ according to the distance T-LA: 0 cm: 84% / 1–2 cm: 84% and 3 cm: 91%. No post operative mortality was noticed with a 15% post operative morbidity rate, same in the two arms. Sterilized specimen rate was respectively 7% and 12.5% (p: 0.29), the mean inferior safety margin and radial margin was 1 cm and 4 mm, same in the two groups as the 90% R0 resection rate. On specimen, nodal involvement rate was 5.6% for pT0–1, 29% for pT2 and 56% for pT3–4. No difference was seen for down-staging between the two groups (p: 0.59). With a 22 months follow up, we noticed 92% rate of stoma closure in the conservative group. Seven patients had a local recurrence and 25 metastases with 12 patient’s death. Conclusions: GRECCAR 1 is the first prospective randomized trial which shows an 85% rate of sphincter conservative surgery due to down staging induced by preoperative tretament. No significant difference was seen between HDR and RTCT with a trend for more morbidity in the first group. Intersphincteric resection is a safe technical procedure in order to preserv the striated sphincter with sufficient lateral and inferior margins. No significant financial relationships to disclose.
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Drukker, Caroline, Marjanka Schmidt, Emiel J. Rutgers, Fatima Cardoso, Karla Kerlikowske, Laura Esserman, Leen Slaets, Jan Bogaerts, and Laura J. van 't Veer. "Breast cancer screening: Biology of tumors detected by analog and digital mammography." Journal of Clinical Oncology 31, no. 15_suppl (May 20, 2013): 587. http://dx.doi.org/10.1200/jco.2013.31.15_suppl.587.
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587 Background: Population-based screening might be associated with a higher likelihood of a (ultra)low risk tumor assessed by the 70-gene signature (MammaPrint) (ultralow defined as indexscore >0.6, no distant metastasis observed at 5 years in the original 78 patients). The aim of this study is to determine the proportion of biologically (ultra)low risk tumors among the screen-detected tumors and to evaluate the impact of the analog versus digital screening technique. Methods: All Dutch breast cancer patients enrolled in the MINDACT trial (EORTC-10041), who were invited for the Dutch screening program (biennial, age 50-75), were included (n=1409). The proportions of 70-gene signature high, low and ultralow risk were calculated for patients with screen-detected (n=775), interval (n=390), and symptomatic, non-screening (n=244) carcinomas, taking into account analog vs. digital technology. Co-variants such as age, tumor size, grade, histological type, ER, HER2 and nodal status were included in the analyses. Results: Among the screen-detected tumors, 31.5% had a high risk, 31.2% a low risk and 37.3% an ultralow risk 70-gene signature result, compared to 47.4%, 28.5% and 24.1% among the interval carcinomas, respectively (p=0.001). Among the screen-detected carcinomas, 40.6% were detected using analog (n=315) and 59.4% using digital mammography (n=459). When using digital imaging a shift was seen among the screen-detected tumors in the proportions of high risk tumors from 27% to 35% and ultralow risk from 42% to 34%, low risk proportions remained the same (31%)(p=0.011). No such difference was seen for other tumor characteristics. Conclusions: Screen-detection was found to be associated with a higher likelihood of a biologically low risk tumor. The transition from analog to digital mammography resulted in a smaller proportion of ultralow risk and a larger proportion of high risk tumors among the screen-detected carcinomas.
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Mu, Xin, Sailong Wu, Lirong Cheng, and H. Y. Fu. "Edge Couplers in Silicon Photonic Integrated Circuits: A Review." Applied Sciences 10, no. 4 (February 24, 2020): 1538. http://dx.doi.org/10.3390/app10041538.
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Silicon photonics has drawn increasing attention in the past few decades and is a promising key technology for future daily applications due to its various merits including ultra-low cost, high integration density owing to the high refractive index of silicon, and compatibility with current semiconductor fabrication process. Optical interconnects is an important issue in silicon photonic integrated circuits for transmitting light, and fiber-to-chip optical interconnects is vital in application scenarios such as data centers and optical transmission systems. There are mainly two categories of fiber-to-chip optical coupling: off-plane coupling and in-plane coupling. Grating couplers work under the former category, while edge couplers function as in-plane coupling. In this paper, we mainly focus on edge couplers in silicon photonic integrated circuits. We deliver an introduction to the research background, operation mechanisms, and design principles of silicon photonic edge couplers. The state-of-the-art of edge couplers is reviewed according to the different structural configurations of the device, while identifying the performance, fabrication feasibility, and applications. In addition, a brief comparison between edge couplers and grating couplers is conducted. Packaging issues are also discussed, and several prospective techniques for further improvements of edge couplers are proposed.
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Rothe, J., G. Angloher, F. Ardellier-Desages, A. Bento, L. Canonica, A. Erhart, N. Ferreiro, et al. "NUCLEUS: Exploring Coherent Neutrino-Nucleus Scattering with Cryogenic Detectors." Journal of Low Temperature Physics 199, no. 1-2 (December 10, 2019): 433–40. http://dx.doi.org/10.1007/s10909-019-02283-7.
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AbstractThe NUCLEUS experiment aims for the detection of coherent elastic neutrino-nucleus scattering at a nuclear power reactor with gram-scale, ultra-low-threshold cryogenic detectors. This technology leads to a miniaturization of neutrino detectors and allows to probe physics beyond the Standard Model of particle physics. A 0.5 g NUCLEUS prototype detector, operated above ground in 2017, reached an energy threshold for nuclear recoils of below 20 eV. This sensitivity is achieved with tungsten transition edge sensors which are operating at temperatures of 15 mK and are mainly sensitive to non-thermal phonons. These small recoil energies become accessible for the first time with this technology, which allows collecting large-statistics neutrino event samples with a moderate detector mass. A first-phase cryogenic detector array with a total mass of 10 g enables a 5-sigma observation of coherent scattering within several weeks. We identified a suitable experimental site at the Chooz Nuclear Power Plant and performed muon and neutron background measurements there. The operation of a NUCLEUS cryogenic detector array at such a site requires highly efficient background suppression. NUCLEUS plans to use an innovative technique consisting of separate cryogenic anticoincidence detectors against surface backgrounds and penetrating (gamma, neutron) radiation. We present first results from prototypes of these veto detectors and their operation in coincidence with a NUCLEUS target detector.
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Tyagi, Priyanka, Sanjay Kumar Singh, and Piyush Dua. "Gate Diffusion Input Based 10-T CNTFET Power Efficient Full Adder." Recent Advances in Electrical & Electronic Engineering (Formerly Recent Patents on Electrical & Electronic Engineering) 14, no. 4 (June 17, 2021): 415–27. http://dx.doi.org/10.2174/2352096514666210106094136.
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Background: Full adder is the key element of digital electronics. The CNTFET is the most promising device in modern electronics. To enhance the performance of the full adder, CNTFET is used in place of the CMOS. Objective: To implement the high speed full adder circuit for advance applications of the digital world. Methods: Full adder circuit with a new Gate diffusion technique has been implemented in this work. This is a comparative study of the 10-T CNTFET full adder with GDI technique and the 10-T Finfet based full adder using GDI technique. Ultra-low-power feature is the additional advantage of the GDI technique. This technology provides the full swing voltage to the circuit. Moreover, it also reduces the number of transistors required. This technique has been used with CNTFET to upgrade the full adder in terms of the dissipated power and product of power consumed and delay introduced in the circuit. Results: The proposed design shows that the low power dissipation comes out to be approximately 4.3nW at 0.5volts. The power delay product is 4.7x10-20 J at the same voltage level. The FinFET design also shows the better performance with GDI. But GDI enhances CNTFET based design power consumption by about 32% from the FinFET. Conclusions: CNTFET showed a better response due to good current conductivity as compared to the FinFET. This work has been implemented and simulated on the 32nm node technology.
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Mazón-Suástegui, José, Joan Salas-Leiva, Andressa Teles, and Dariel Tovar-Ramírez. "Immune and Antioxidant Enzyme Response of Longfin Yellowtail (Seriola rivoliana) Juveniles to Ultra-diluted Substances Derived from Phosphorus, Silica and Pathogenic Vibrio." Homeopathy 108, no. 01 (November 20, 2018): 043–53. http://dx.doi.org/10.1055/s-0038-1672197.
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Background This research aimed to observe the effect of homeopathic treatments prepared from Vibrio parahaemolyticus and V. alginolyticus (H1) and commercial homeopathic medication Phosphoricum acidum and Silicea terra (H2) on the immune and antioxidant response in Seriola rivoliana juveniles under usual culture conditions and challenged with V. parahaemolyticus. Materials and Methods Quantitative polymerase chain reaction analysis was used to study changes in the expression of key genes related to immune response, cytokines (interleukin-1β [IL-1β]), adapter protein for cytokine release (MyD88) and piscidin and spectrophotometric techniques to analyze the activity of antioxidant superoxide dismutase (SOD) and catalase (CAT) enzymes in Seriola rivoliana juveniles at 30 (weaning stage [WS]) and 60 (early juveniles [EJ]) days post-hatching. Results The H1 treatment led to over-expression of the IL-1β and MyD88 genes in fish at WS and EJ with respect to control, contrary to the H2 treatment that led to under-expression of the IL-1β, MyD88 and piscidin genes at the EJ stage. In fish challenged with V. parahaemolyticus, both H1 and H2 led to over-expression of IL-1β and MyD88; H2 caused an over-expression of piscidin. The SOD activity was higher in H1 with respect to H2 and the control group. CAT remained relatively stable with both H1 and H2 treatments. Conclusions The results suggest that the overall effect of H1 was due to the presence of unknown antigens in low concentrations, while the response to H2—specifically during challenge—may have been due to a stimulating effect of nano-structures, prevailing from mother tincture after sequential dilution/succussion, in a pathway similar to that attributed to nano-vaccines.
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Mandat, Dusan, Toshihiro Fujii, Max Malacari, John Farmer, Xiaochen Ni, Paolo Privitera, Justin Albury, et al. "Atmospheric monitoring with the Fluorescence detector Array of Single-pixel Telescopes." EPJ Web of Conferences 197 (2019): 02002. http://dx.doi.org/10.1051/epjconf/201919702002.
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The Fluorescence detector Array of Single-pixel Telescopes (FAST) is a proposed low-cost, largearea, next-generation experiment for the detection of ultrahigh-energy cosmic rays (UHECRs) via the atmospheric fluorescence technique. Two FAST telescopes are currently installed and operating at the Black Rock Mesa site of the Telescope Array Experiment in Utah, USA. Knowledge of the properties of the atmosphere above the detector is of utmost importance for the analysis and reconstruction of the energy and trajectory of UHECRs measured with an atmospheric fluorescence telescope. The FAST experiment uses all sky camera (FASCam) and sky quality monitor (SQM) for the detection of clouds and quantification of the night-sky background light in the field-of-view of the telescopes. Measurements of a vertically-fired ultra-violet laser at a distance of 21 km from the FAST telescopes are used to infer the transparency of the atmosphere above the detector through comparison with simulations.
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Anerao, Ajit, Vishal Solase, Thaksen Gadhave, Amol More, and Nitin Pradhan. "Quantification of Genotoxic Impurities in Key Starting Material of Sertraline Hydrochloride by Simple and Sensitive Liquid Chromatography Technique." Current Pharmaceutical Analysis 16, no. 1 (December 20, 2019): 110–16. http://dx.doi.org/10.2174/1573412914666180716160507.
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Background: Schiff base is an advanced key starting material of Sertraline hydrochloride. Schiff base is synthesized using two raw materials 1-Naphthol and 1,2-Dichlorobenzene which are potentially genotoxic impurities. Objective: Genotoxic impurities need to be controlled in key starting material to avoid carry forward in the active pharmaceutical ingredient. For trace level quantification of impurities a sensitive, accurate and cost effective method is developed by simultaneous estimation of both impurities. Methods: Reverse phase high performance liquid chromatography (HPLC) method was developed and validated for determination of both impurities in Schiff base. HPLC column Cosmosil MS-II C18, 100 mm X 4.6 mm, 3 μm particle size with ultra-violet detector (UV) was used. Results: The calibration curve of 1-Naphthol and 1,2-Dichlorobenzene showed good linearity over the concentration range of 0.25 µg/g to 7.5 µg/g and 1.5 µg/g to 7.5 µg/g and the regression coefficient was 0.999 and 0.998 respectively. Method had very low limit of detection (LOD) and limit of quantification (LOQ) of both analytes which proves that the method is sensitive and suitable for quantification of compounds at trace level. Conclusion: The proposed method is specific, linear, accurate, rugged and precise. Genotoxic impurities 1-Naphthol and 1,2-Dichlorobenzene are quantified and controlled in the key starting material of Sertraline hydrochloride. The validated method can be used in quality control unit in pharmaceutical industry.
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Leng, K., J. Korenaga, and T. Nissen-Meyer. "3-D scattering of elastic waves by small-scale heterogeneities in the Earth’s mantle." Geophysical Journal International 223, no. 1 (July 8, 2020): 502–25. http://dx.doi.org/10.1093/gji/ggaa331.
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SUMMARY Small-scale heterogeneities in the Earth’s mantle, the origin of which is likely compositional anomalies, can provide critical clues on the evolution of mantle convection. Seismological investigation of such small-scale heterogeneities can be facilitated by forward modelling of elastic wave scattering at high frequencies, but doing so with conventional 3-D numerical methods has been computationally prohibitive. We develop an efficient approach for computing high-frequency synthetic wavefields originating from small-scale mantle heterogeneities. Our approach delivers the exact elastodynamic wavefield and does not restrict the geometry or physical properties of the local heterogeneity and the background medium. It combines the technique of wavefield injection and a numerical method called AxiSEM3D. Wavefield injection can decompose the total wavefield into an incident and a scattered part. Both these two parts naturally have low azimuthal complexity and can thus be solved efficiently using AxiSEM3D under two different coordinate systems. With modern high-performance computing (on an order of magnitude of 105 CPU-hr), we have achieved a 1 Hz dominant frequency for global-scale problems with strong deep Earth scattering. Compared with previous global injection approaches, ours allows for a 3-D background medium and yields the exact solution without ignoring any higher-order scattering by the background medium. Technically, we develop a traction-free scheme for realizing wavefield injection in a spectral element method, which brings in several flexibilities and simplifies the implementation by avoiding stress or traction computation on the injection boundary. For a spherical heterogeneity in the mid-lower mantle, we compare the 3-D full-wave solution with two approximate ones obtained, respectively, by the perturbation theory and in-plane (axisymmetric) modelling. As a comprehensive application, we study S-wave scattering by a 3-D ultra-low velocity zone, incorporating 3-D crustal structures on the receiver side as part of the background model.
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Laipan, A. Sh, S. P. Morozov, L. A. Nizovtsova, I. A. Blokhin, and V. A. Gombolevsky. "Ulltra-low-dose computed tomography in the diagnosis of diseases of the paranasal sinuses in pediatric population: literature review." Medical Visualization 25, no. 3 (September 18, 2021): 109–18. http://dx.doi.org/10.24835/1607-0763-908.
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Background. Sinonasal diseases are widespread in childhood. Radiological studies, including computer tomography, are an optimal and effective method of diagnosis. The child's body is more sensitive to radiation exposure than adults. The threshold of exposure, which may induce internal organs injury in children, requires a precise selection of the radiological method with minimal radiation dose. There is currently no unified position in the professional community on the appropriateness of the use of ultra-low-dose computed tomography in pediatrics.We reviewed the data on the appropriateness and effectiveness of paranasal low-dose computed tomography in pediatrics.Materials. 57 domestic and foreign publications, for the period from January 2001 to November 2019. In order to achieve the objective, we analyzed relevant domestic and foreign publications in scientific libraries e-LIBRARY, PubMed, Google Scholar per the keywords: “low-dose CT”, “children”, “paranasal sinus”, “pediatric”, “diagnosis”, “children”, “low-dose computed tomography”, “sinusitis”, “paranasal sinuses”.Results. The analysis of the available literature allowed summarizing the current data on pediatric paranasal disease diagnostics and the use of computed tomography, as well as to identify possible options for reducing radiation dose.Conclusions. Conducting many radiological examinations in a child leads to the risk of cancer. However, these examinations are an effective way to diagnose paranasal diseases, and a CT scan is the “gold standard”. The actual task is to develop a CT technique with reduced radiation exposure without compromising image quality. The need to review and optimize the standard protocols of radiological studies to determine the efficacy and feasibility of studies with minimal radiation exposure to children is justified.
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Ahmad, Niyaz, Rizwan Ahmad, Atta Naqvi, Md Alam, Rehan Abdur Rub, and Farhan Ahmad. "Enhancement of Quercetin Oral Bioavailability by Self-Nanoemulsifying Drug Delivery System and their Quantification Through Ultra High Performance Liquid Chromatography and Mass Spectrometry in Cerebral Ischemia." Drug Research 67, no. 10 (May 23, 2017): 564–75. http://dx.doi.org/10.1055/s-0043-109564.
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Abstract Background Quercetin (Qur) and its major in vivo bioactive metabolites i. e., 3′-O-methyl quercetin, 4′-O-methyl quercetin and quercetin 7-O-β-D-glucuronide, may be used to treat cerebral ischemia however the poor aqueous solubility and less intestinal absorption of Qur results low bioavailability. Purpose To improve Qur bioavailability through preparation of nanoformulation and to develop and validate a sensitive quantification method for Qur detection in brain homogenate. Methods Qur-containing self-nanoemulsifying drug delivery system (Qur-SNEDDS) was developed to form oil-in-water nanoemulsions in situ. Ultra-high performance liquid chromatography electrospray ionization-synapt mass spectrometric method (UHPLC/ESI-QTOF-MS/MS) was developed and validated for quantification whereas for optimal recovery of analyte, a liquid-liquid extraction method (LLE) was used. Results A droplet size of 94.63±3.17 nm and zeta potential of −17.91±1.02 mV for nanoemuslion, elution time for Qur and internal standard (IS) Rutin as 1.21 and 1.50 min alongwith a transition at m/z 301.04/151.03 and 609.21/299.21, were observed respectively. Similarly, linear dynamic range (1.00 ng/mL–2 000.0 ng/mL), intra and inter-assay i. e., %CV of 0.26–2.04, lower limit of detection (LOD) 0.08 ng/mL as well as lower limit of quantitation (LOQ) as 0.131 ng/mL were also observed. Conclusion The developed method have advantage over previous all methods i. e., less time consuming (<3.0), low consumption of solvents (flow rate 0.20 mL/min.) via small size column, more accuracy and specificity as well as use of acetonitrile as compared to hazardous solvents. This certainly adds advantages for green chromatography technique and supports application of current developed method for quantification and evaluation of Qur-SNEDDS.
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Fareed, Jawed, Angel Gray, Daniel Kahn, Josephine Cunanan, Hussein Khan, Christian Viskov, and Debra Hoppensteadt. "The effect of tissue factor pathway inhibitor release and interactions with growth factors on the antitumor effects of ultra low molecular weight heparin semuloparin." Journal of Clinical Oncology 30, no. 15_suppl (May 20, 2012): e13117-e13117. http://dx.doi.org/10.1200/jco.2012.30.15_suppl.e13117.
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e13117 Background: Heparins are known to produce anti-tumor effects beside other pharmacologic actions. More recently an ultra LMWH has been developed for the prevention of thrombosis in cancer patients. Initial studies demonstrated that this agent also exhibits anti-tumor effects in animal models. To understand the mechanism of anti-tumor effects of this agent studies were designed to fractionate this ULMWH in to various AT affinity fractions. Methods: An ULMWH (semuloparin, Sanofi-aventis) and its high (HAF) and low (LAF) affinity fractions were prepare by AT affinity chromatography. These agents were administered at 1 mg/kg to primates via intravenous route. Blood samples were collected for a period of up to 6 hours. TFPI release and anti-Xa activities were measured. The interactions of ULMWH and its fractions with various growth factors such as FGF, VEGF, EGF and beta TGF were measured using a mass spectral method employing SELDI technique. The anti-tumor effects of each of these agents were measured using the mouse model of Lewis lung carcinoma. Results: In comparison to ULMWH the LAF showed minimal anti Xa activity whereas HAF exhibited a higher activity. All agents exhibited a similar release of the TFPI; however, HAF exhibited slightly higher release. All agents also showed varying degrees of binding to growth factors as measured by peak intensities. All agents produce anti-tumor effects in the mouse model resulting in a significant reduction in tumor size. Conclusions: Semuloparin has been clinically proven to prevent venous thromboembolism in patients with cancer (SAVE ONCO). These effects are attributable to the inhibition of factor Xa and the generation of thrombin. The fact that LAF mediates its anti-tumor effects without producing anti Xa effects suggest that these may be related to the release of TFPI. Furthermore the ULMWH, HAF and LAF all interact with growth factors suggest that these interactions may also contribute to anti-tumor effects of semuloparin, therefore, beside antithrombotic effects this agent also exhibits oncostatic effects.
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Georgy, Bassem. "Comparison Between Radiofrequency Targeted Vertebral Augmentation and Balloon Kyphoplasty in the Treatment of Vertebral Compression Fractures: Addressing Factors that Affect Cement Extravasation and Distribution." Pain Physician 5;16, no. 5;9 (September 14, 2013): E513—E518. http://dx.doi.org/10.36076/ppj.2013/16/e513.
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Background: Both vertebroplasty and balloon kyphoplasty have been described for treatment of vertebral compression fractures. Vertebroplasty is known for its high leakage rate compared with balloon kyphoplasty. In vitro studies have shown that high-viscosity cements significantly decrease the incidence of cement leakage and increase the predictability of cement fill in cancellous bonelike substrates compared with low-viscosity cements. Objective: This study compares the incidence and pattern of cement leakage in cases treated with standard balloon kyphoplasty (BKP) and a novel vertebral augmentation procedure, radiofrequency targeted vertebral augmentation (RF-TVA). Study Design: Retrospective evaluation of postoperative radiographs. Setting: Single center inpatient and outpatient population. Methods: Two methods of vertebral augmentation were utilized. Conventional bipedicular BKP and RF-TVA, a novel unipedicular technique which uses a navigational osteotome to create targeted, bone sparing cavities and RF energy to deliver an ultra-high viscosity cement at a consistent rate via a remote controlled, automated hydraulic delivery system. Postoperative radiographs of patients treated with the 2 techniques were critically analyzed for the incidence and location of cement leakage. Eighty consecutive patients with 106 treated levels were included. Thirty-five patients with 49 levels in the BKP and 45 patients with 57 levels in RF-TVA group were evaluated. Results: Leakages less than 1-2 mm were not reported since they may not represent any clinical significance. In the BKP group, 6 leakages (12%) were reported (3 discal, 2 venous, one paravaertebral, and no epidural). In the RF-TVA group, a total of 3 leakages (5%) were reported, (one discal, 2 venous, no paravaertebral or epidural). Using contingency analysis for leakage per level, there was a statistical difference for leakage between RF-TVA and standard BKP, P < 0.01. Limitations: Retrospective study, single center. Conclusions: The RF-TVA technique may provide an approximately 50% reduction in leakage rate when compared to standard BKP. This may be related to the combination of controlled delivery of radiofrequency activated (high viscosity) cement at a fixed, low rate of delivery into sitespecific channels created using a navigational osteotome. Additionally, based on the unipedicular access and remotely controlled cement delivery RF-TVA may decrease procedural invasiveness and physician radiation exposure, respectively. Institutional Review: This study was approved by the Institutional Review Board. Key words: Balloon kyphoplasty, radiofrequency targeted vertebral augmentation, compression fractures, cement leakage
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Huang, Chen-Ji, Gudivada Vijaya Narasimha, Yu-Cheng Chen, Jen-Kun Chen, and Guo-Chung Dong. "Measurement of Low Concentration of Micro-Plastics by Detection of Bioaffinity-Induced Particle Retention Using Surface Plasmon Resonance Biosensors." Biosensors 11, no. 7 (July 3, 2021): 219. http://dx.doi.org/10.3390/bios11070219.
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The issue of micro-plastics is becoming more and more important due to their ubiquity and the harm they cause to the human body. Therefore, evaluating the biological–physical interaction of micro-plastics with health cells has become the focus of many research efforts. This study focuses on the movement mode and low concentration detection development for micro-plastics in surface plasmon resonance (SPR). Firstly, 20-micrometer micro-plastics were prepared by grinding and filtering, and the movement mode was explored; then, the characteristics were investigated by SPR. Chromatographic analysis showed that the surface charge of micro-plastics dominated the elution time, and estrogen receptors (ERs) played a supporting role. A difference of micro-plastics in SPR sensorgram was observed, inferring the micro-plastics’ movement in rolling mode on the ERs. Characteristics analysis indicated that the low particle number of micro-plastics on SPR showed a linear relationship with the response unit (RU). When ERs were immobilized on the biosensor, the force of the binding of micro-plastics to ERs under an ultra-low background was equivalent to the dissociation rate constant shown as follows: PS (0.05 nM) > PVC (0.09 nM) > PE (0.14 nM). The ELISA-like magnetic beads experiment verified the specificity between ERs and micro-plastics. Therefore, by using the SPR technique, a biological-derived over-occupation of PS was found via higher binding force with ERs and longer retention time. In the future, there will be considerable potential for micro-plastics issues, such as identification in natural samples, biomarking, real-time detection in specific environments/regions and human health subject.
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Rohani, Fatemeh Ganjeizadeh, and Mehdi Ansari. "Electropolymerized MIP with MWCNTs on Stir Bar Using Multivariate Optimization for Tetradifon Detection in Date." Pharmaceutical Nanotechnology 7, no. 5 (October 15, 2019): 404–17. http://dx.doi.org/10.2174/2211738507666190919113100.
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Background: Multi-walled carbon nanotubes (MWCNT) adjunct to molecularly imprinted polymers (MIP) have advantages of the large surface area of nanoparticles and selectivity of MIPs for selective extraction of tetradifon as a widely used pesticide in date palm. Objectives: The main aims were the use of experimental design, electrochemical synthesis and ultra-high performance liquid chromatography (UHPLC) to develop a simple, reliable and precise pesticide residue analysis method as an important aspect of food and drug quality control for the determination of tetradifon in date palms. Methods: An MIP in the presence of MWCNT was synthesized by cyclic voltammetric technique on a steel rod to produce a composite of MIP-MWCNTs for stir bar extraction of tetradifon residue in date samples. The experimental design was used to optimize MIPMWCNT composite synthesis through the screening of eight variables. The composite was characterized by scanning electron microscopy (SEM). Tetradifon was determined in extracted samples by UHPLC under optimum conditions. Results: A very thin film was made by MIP-MWCNT coated on a steel rod which was repeatable and had good adhesion and persistence. The detection limit (LOD) and the quantification limit (LOQ) of the method were measured as 16 and 49 ng/ml, respectively. Average recovery of tetradifon at the two spiked levels was observed to be as low as 86.5% to 90.7% (RSD from 0.79% to 1.04%). Conclusion: The low cost, high selectivity, good reproducibility, acceptable intra and inter day precision and accuracy developed method were successfully applied to determine tetradifon residue in date samples purchased from a local market.
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Lin, Chuangxin, Vadim Monteiller, Kai Wang, Tianshi Liu, Ping Tong, and Qinya Liu. "High-frequency seismic wave modelling of the deep Earth based on hybrid methods and spectral-element simulations: a conceptual study." Geophysical Journal International 219, no. 3 (September 12, 2019): 1948–69. http://dx.doi.org/10.1093/gji/ggz413.
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SUMMARY Over the past few decades, seismic studies have revealed complex structural anomalies in the Earth’s deep interior at various scales, such as large low-shear-velocity provinces (LLSVPs) and ultra-low velocity zones (ULVZs) in the lowermost mantle, and small-scale scatterers in the mid-mantle. These structures which are critical for better understanding of the geodynamics and evolution of the deep Earth, need to be further resolved by high-resolution imaging techniques. The spectral-element method (SEM) can be used to accurately simulate seismic wave propagation in heterogeneous Earth models, and its application in full-waveform inversion (FWI) provides a promising high-resolution and high-fidelity imaging technique. But it can be computationally prohibitive when used to model small scale structures in the deep Earth based upon high-frequency seismic waves. The heavy computational cost can be circumvented by using hybrid methods, which restrict the main computation by SEM solver to only a small target region (e.g. above the CMB) encompassing possible 2-D/3-D anomalies, and apply efficient analytical or numerical methods to calculate the wavefield for 1-D background models. These forward modelling tools based on hybrid methods can be then used in the so-called ‘box tomography’ approach to resolve fine-structures in the deep Earth. In this study, we outline the theory of a hybrid method used to model small scale structures in the deep Earth and present its implementation based on SEM solvers in a three-step workflow. First, the wavefield generated by the source is computed for the 1-D background model with traction and velocity saved for the virtual boundary of the target region, which are then used as boundary inputs to simulate the wavefield in the target region based on absorbing boundary condition in SEM. In the final step, the total wavefield at receivers is reconstructed based upon the total wavefield on the virtual boundary computed in the previous step. As a proof-of-concept study, we demonstrate the workflow of the hybrid method based on a 2-D SEM solver. Examples of the hybrid method applied to a coupled fluid–solid model show that our workflow can accurately recover the scattered waves back to the surface. Furthermore, we benchmark the hybrid method on a realistic heterogeneous Earth model built from AK135-F and show how teleseismic scattered waves can be used to model deep Earth structures. By documenting the theory and SEM implementation of the hybrid method, our study lays the foundation for future two-way coupling of 3-D SEM solver with other efficient analytic or numerical 1-D solvers.
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Spuler, Scott M., Matthew Hayman, Robert A. Stillwell, Joshua Carnes, Todd Bernatsky, and Kevin S. Repasky. "MicroPulse DIAL (MPD) – a diode-laser-based lidar architecture for quantitative atmospheric profiling." Atmospheric Measurement Techniques 14, no. 6 (June 21, 2021): 4593–616. http://dx.doi.org/10.5194/amt-14-4593-2021.
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Abstract. Continuous water vapor and temperature profiles are critically needed for improved understanding of the lower atmosphere and potential advances in weather forecasting skill. Ground-based, national-scale profiling networks are part of a suite of instruments to provide such observations; however, the technological method must be cost-effective and quantitative. We have been developing an active remote sensing technology based on a diode-laser-based lidar technology to address this observational need. Narrowband, high-spectral-fidelity diode lasers enable accurate and calibration-free measurements requiring a minimal set of assumptions based on direct absorption (Beer–Lambert law) and a ratio of two signals. These well-proven quantitative methods are known as differential absorption lidar (DIAL) and high-spectral-resolution lidar (HSRL). This diode-laser-based architecture, characterized by less powerful laser transmitters than those historically used for atmospheric studies, can be made eye-safe and robust. Nevertheless, it also requires solar background suppression techniques such as narrow-field-of-view receivers with an ultra-narrow bandpass to observe individual photons backscattered from the atmosphere. We discuss this diode-laser-based lidar architecture's latest generation and analyze how it addresses a national-scale profiling network's need to provide continuous thermodynamic observations. The work presented focuses on general architecture changes that pertain to both the water vapor and the temperature profiling capabilities of the MicroPulse DIAL (MPD). However, the specific subcomponent testing and instrument validation presented are for the water vapor measurements only. A fiber-coupled seed laser transmitter optimization is performed and shown to meet all of the requirements for the DIAL technique. Further improvements – such as a fiber-coupled near-range receiver, the ability to perform quality control via automatic receiver scanning, advanced multi-channel scalar capabilities, and advanced processing techniques – are discussed. These new developments increase narrowband DIAL technology readiness and are shown to allow higher-quality water vapor measurements closer to the surface via preliminary intercomparisons within the MPD network itself and with radiosondes.
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Sukul, Nirmal Chandra, Tandra Sarkar, Atheni Konar, and Anirban Sukul. "Proteins as targets for high dilutions of drugs: Interaction between ?-amylase and mercuric chloride." International Journal of High Dilution Research - ISSN 1982-6206 17, no. 2 (July 16, 2021): 24–25. http://dx.doi.org/10.51910/ijhdr.v17i2.920.
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Background: High dilutions of drugs, used in homeopathy, are usually applied by oral route or foliar spray. These dilutions first come in contact with membrane or circulating proteins. Ultra low doses of mercuric chloride, called potencies, promote activity of diastase or ?-amylase in terms of breakdown of starch, a polysaccharide into a disaccharide maltose in a cell-free medium in test tubes. Merc cor or HgCl2 in high doses inhibits the enzyme activity.
Aims: To see (i) whether the high and ultra low dose effects of HgCl2 involve different binding sites of the enzyme and (ii) to find an explanation for the low dose effect of HgCl2 in spite of absence of its original molecules.
Methodology: Merc cor mother tincture (147 mM HgCl2) in distilled water was used undiluted in this experiment. Merc cor 200c and 1000c were prepared from the mother tincture (MT) by successive dilution with water 1:100 followed by succussion in 200 and 1000 steps, respectively, and finally preserved in 90% EtOH. These potencies and blank 90% ethanol, were diluted with deionized, distilled (DD) water 1:1000 to minimize ethanol content in test solutions. Each test solution or control was mixed with the enzyme 1:10 just before experiment. The control consisted of DD water. An isothermal calorimetry (ITC) instrument was used to measure the interaction between soluble starch and ?-amylase mixed with each potency (200c/1000c) of Merc cor, its mother tincture, ethanol and control. ITC is a thermodynamic technique which helps in measuring directly very small amount of heat evolved during chemical reaction. Soluble starch 90 µM was injected into 300 µl of 15µM ?-amylase at 2 µl / injection. Twenty injections, one every 2 min, were given. The enzyme substrate interaction in terms of heat released (exothermic) or absorbed (endothermic) were monitored by the ITC instrument. All ITC measurements were calculated and analyzed statistically by an in-built software Origin 7.
Results and discussion: The data are presented in figures. While Merc cor MT shows endothermic reaction, all its potencies, ethanol and water control show exothermic reactions. There is wide variation in enthalpy (?H), entropy (?S), binding constant (K) and Gibbs free energy change (?G) among the treatments with Merc cor MT, potencies, ethanol and also control. The results indicate that Merc cor MT and its potencies act on different binding sites of the enzyme. The variation in thermodynamic parameters suggest difference in binding interaction between the drug solutions and the enzyme. This in turn influences the enzyme substrate interaction as reported in earlier studies. The potencies are virtually water modified by the starting substance HgCl2.
Conclusion: The mother tincture and potencies of mercuric chloride produce different effects on the enzyme substrate interaction. Potencies show wide variation in ?H, ?S, K and ?G values. It appears from the results that the drugs used in homeopathy produce dual action on proteins. At high doses they act on a binding site(s) but at ultra low doses they act on a different binding site(s). Proteins in an organism may serve as targets for initiation of action of homeopathic potencies.
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Dudkin, F., B. R. Arora, V. Korepanov, O. Leontyeva, and A. K. Sharma. "Application of polarization ellipse technique for analysis of ULF magnetic fields from two distant stations in Koyna-Warna seismoactive region, West India." Natural Hazards and Earth System Sciences 10, no. 7 (July 12, 2010): 1513–22. http://dx.doi.org/10.5194/nhess-10-1513-2010.
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Abstract. A new approach is developed to find the source azimuth of the ultra low frequency (ULF) electromagnetic (EM) signals believed to be emanating from well defined seismic zone. The method is test applied on magnetic data procured from the seismoactive region of Koyna-Warna, known for prolonged reservoir triggered seismicity. Extremely low-noise, high-sensitivity LEMI-30 search coil magnetometers were used to measure simultaneously the vector magnetic field in the frequency range 0.001–32 Hz at two stations, the one located within and another ~100 km away from the seismic active zone. During the observation campaign extending from 15 March to 30 June 2006 two earthquakes (EQs) of magnitude (ML>4) occurred, which are searched for the presence of precursory EM signals. Comparison of polarization ellipses (PE) parameters formed by the magnetic field components at the measurement stations, in select frequency bands, allows discrimination of seismo-EM signals from the natural background ULF signals of magnetospheric/ionospheric origin. The magnetic field components corresponding to spectral bands dominated by seismo-EM fields define the PE plane which at any instant contains the source of the EM fields. Intersection lines of such defined PE planes for distant observation stations clutter in to the source region. Approximating the magnetic-dipole configuration for the source, the magnetic field components along the intersection lines suggest that azimuth of the EM source align in the NNW-SSE direction. This direction well coincides with the orientation of nodal plane of normal fault plane mechanism for the two largest EQs recorded during the campaign. More significantly the correspondence of this direction with the tectonic controlled trend in local seismicity, it has been surmised that high pressure fluid flow along the fault that facilitate EQs in the region may also be the source mechanism for EM fields by electrokinetic effect.
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Heusser, G. "Low-Radioactivity Background Techniques." Annual Review of Nuclear and Particle Science 45, no. 1 (December 1995): 543–90. http://dx.doi.org/10.1146/annurev.ns.45.120195.002551.
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